Burglar-alarm.



No. 647,412. Patented Apr. l0, I900. H. c. JOHNSON.

BURGLAR ALARM. 7

(Application filed Dec. 7, 1899.)

(N0 Model.)

Invezafaz Jlwzy Cmfdzmam VNITED STATES PATENT 'OFFICE.

lIENRY CLAY JOHNSON, or WASHINGTON, DISTRICT OF COLUMBIA.

BURGhAR-ALARM;

sPEoIFIoArIo rbrmin part of Letters rateiit N6. 647,412, dated 1 m 10,1960. Application filed December 7, 1899. Serial N01 739,570. (Nomodel.)

T0 at whom it may concern:

Be it known that I, HENRY CLAY JOHNSQN, a citizen of the United States,residing at Washington, District of Columbia, have invented new anduseful Improvements in Burglar-Alarms, of which the followingis aspecification.

My invention relates to burglar'alarms, the object of the same being toprovide a simple and cheaply-constructed device of this kind which maybe readily carried in the pocket and which may be readily applied, so asto be thrown into operation by the opening of a door or window. 1

The invention consists of a bell or other signaling device having alongitudinally-movable push-bar for actuating the same and atripping-bar having two angularly-arranged arms, one of which isremovably attached to said push-bar and the other is located beneath adoor or other moving part.

It also consists in certain features and details of construction andcombinations -of parts, which will be hereinafter more fully describedand claimed.

In the drawings forming part of this specification, Figure 1 is aperspective view of the alarm. Fig. 2 is a similar View of thetripping-bar therefor. Fig. 3 is a sectional view showing theapplication of my invention. Fig. 4 is a horizontal section, on anenlaged scale, on the line as w of Fig. 3; and Fig. 5 is a similarsection on the line y y of Fig. 8.

Like reference-numerals indicate like parts in the different views.

The alarm mechanism is mounted in a casing made up of a cup-shapedbottom 1, having a plurality of pointed prongs or projections 2 2 on itsunder side, provided for engagement with the floorof the room, on whichthe device is placed, and a substantiallyhemispherical bell 3,constituting a hood or cover. Secured within the cup 1, in line with theupper edge thereof, is a disk 4, which provides a closed compartment atthe lower end of the casing, and secured to the disk 4 upon posts orstandards 5 5 is a smaller disk 6, as clearly shown. Mounted centrallyof the easing and having bearings in" the disks 4 and 6 is a shaft 7,having a screw-threaded upper end 8. The bell 3 is formed atits centerand on the inside thereof with an in ternally-screwthreaded boss 9, inwhich the screw-threaded upper end 8 of the shaft 7 fits. The said bellis secured in place by screwing the same upon the upper end of saidshaft and may be provided, if desired, with a milled rib or bead 10 forfacilitating the turning of said bell. Secured to a post 11 in the cup 1beneath the disk at is a motor-spring 12, the opposite or free end ofsaid spring being attached to the central shaft 7, heretofore referredto. This spring when wound up by turning the hell 3 to the right holdsthe shaft 7 under tension and causes the same to be rotated. Secured tothe upper end of the shaft 7 is a ratchet-wheel13, and loose upon saidshaft or upon the hub of said ratchet wheel is a gear-wheel 14, the saidgear-wheel carrying a pivoted pawl 15, which is adapted to engagetheteeth of the ratchetwheel13and is held normally in contact with saidteeth by means of a spring 16. The gearwheel 14 is in gear with thestar-wheel 17 through the pinion 18, gear-wheel 19, and pinion 20, thelatter being secured to said starwheel. Cooperating with thestar-wheel17 is a pivotally-mounted esoapement 21, which has secured toit the curved arm 22 of the clapper or hammer 23 of the bell. Secured atone end within the cup 1 beneath the disk 4 is a locking-spring 24.,having a lug or projection 25 thereon,'which extends up through a slot26 in the disk 4 and engages the clapper-arm 22. Through this engagementof the log or projection 25 with the arm 22 the spring 23 serves toprevent the rocking movement of the escapement 21, and consequentlylocks the motor-spring and the gearing connected therewith and rendersthe device inoperative. Oonnected to the free end of the spring 24 andextending outwardly through an opening 27in the cup 1 is a push-rod 28,which when forced inwardly throws the lug 25 out of engagement with thearm 22 and permits the motor-spring 12, through the gearing described,to rock the escapement 21and the clapper 23, connected therewith, andactuate the alarm. The outer end of the bar 28 is recessed on oppositesides, as shown at 29, and has secured to it a plate 30, whose oppositeends are bent inwardly to form flanges 31. Cooperating with the partsabove described in the application of the device as illustrated in thedrawings is a trip-bar 32, bent to form of the arm 33 is insertedbeneath the door 36 and between the lower edge thereof and the sill 37.When applied in the manner described, the arm 34 lies in asubstantiallyvertical position,while the arm 33 is inclined, as shown.If the door 36 be opened, however, the lower edge thereof will ride uponI the upper surface of the arm 33 of the tripping bar and cause a slightlongitudinal movement to be imparted to the opposite, end of said bar.The result is that through the connection between the arm 34 and thepushbar 28 the latter will be forced inwardly, carrying the spring 24and moving the lug 25 on said spring out of engagement with theclapper-arm 22, permitting the motor-spring 12 to actuate the clapperand sound the alarm.

It will be obvious that to wind up the motor-spring 12 it is merelynecessary to turn the bell 3 to the right. The same being connected tothe shaft 7 will rotate said shaft and the ratchet-wheel 13, securedthereto, increasing the tension of said spring and preventing theunwinding thereof, except through the gearing described, through theengagement of the teeth or said ratchet-wheel with the pawl 15 on thegear-wheel 14.

While I have described my invention as being adapted for use inconnection with a door,

it is obvious that the same may be employed in connection withwindow-sashes or other movable parts, all that is necessary being toprovide means whereby the opening of the sash or other movable part willcause the pushbar 28 to be forced inwardly, so as to release the lug 25from the clapper-arm 22.

The device is extremely simple in construction and may be readilycarried in the pocket or in a valise, and for this reason isparticularly adapted for use by traveling men. All that is necessary inorder to place the same in operative position is to place the alarm sothat the prongs or projections 2 on the under side thereof engage theupper surface of the floor or the carpet thereon to prevent the lateralmovement of the device and afterward ap plying the trip-bar 22 byplacing the short arm 34 thereof between the flanges 31 of the disk 30and the long arm 33 thereof between the door 36 and its sill 37.

It will be understood, of course, that my improved alarm may be operatedwithout the use of the tripping-bar 32, all that is necessary being toso locate the alarm mechanism that the push-bar 28 will be actuated bythe opening of a door, Window, or other movable part. When thetripping-bar 32 is employed, however, as illustrated in Fig. 3 of thedrawings, it serves not only to actuate the alarm, but as a stop forpreventing the opening ofthe door.

The prongs or projections 2 on the under side of the casing in which thealarm mechanism is mounted are provided, as heretofore stated, foranchoring the alarm mechanism and preventing the lateral movementthereof. The number of prongs may of course be varied; but four is asatisfactory number to use in that it enables me to locate one of thesame beneath push-bar 28, properly support all the other parts, andprevent the tilting of the easing by the depression of the short arm ofthe tripping-bar 32, which is in engagement with said push-bar. Theseprongs or projections may be formed with threaded shanks, which engagecorresponding openings in the disk 4 and serve to secure the latter inplace.

Having now described my invention, what I claim as new, and desire tosecure by Letters Patent, is-

1. The combination with a burglar-alarm having a longitudinally-movablepush-bar for actuating the same, of a tripping-bar having twoangularly-arranged arms, one of which is attached to said push-bar andthe other is adapted to be inserted beneath a door or other moving part,whereby when said door is opened a longitudinal movement will beimparted to said tripping-bar.

2. A burglar-alarm comprising a signaling device, a motor therefor, alock for rendering said motor inoperative, longitudinally-movablereleasing means forsaid lock, and a tripv ping-bar for actuating saidreleasing means having two angularly-arranged arms, one of which isadapted to be engaged by a door or other moving part, whereby when saiddoor is opened, a longitudinal movement will be im-' parted to saidtripping-bar.

3. A burglar-alarm comprising a bell, a motor-spring, a system ofgearing including an escapement, a clapper for said bell connected withsaid escapement, a locking-spring adapted to engage the clapper-arm forrendering the motor-spring inoperative, means for releasing saidlocking-spring and a tripping-bar for actuating said releasing meanshaving two angularlyarranged arms, one of which is adapted to beinserted beneath and engaged by a door or other moving part.-

4. A burglar-alarm comprising a bell, a motor-spring, a system ofgearing including an escapement, a clapper for said bell connected withsaid escapement, a locking-spring adapted to engage the clapper-arm forrendering the motor-spring inoperative, a push-bar connected with saidlocking-spring for moving the same out of engagement with saidclapper-arm, and a removable tripping-bar attached to said push-bar andhaving an inclined arm adapted to be inserted beneath a door or othermovable part, whereby when said door is opened a longitudinal movementwill be im parted to said tripping-bar for actuating said push-bar.

5. A burglar-alarm comprising a bell, a motor-spring, a system ofgearing, including an escapement, a clapper for said bell connected tosaid escapement, a locking-spring having a lug or projection thereonadapted to engage the clapper-arm for rendering said motorspringinoperative, a push-bar connected to said locking-spring for moving saidlug out of engagement with said clapperarn1;ap1ate secured to the outerend of said push-bar having inwardly-extending flanges thereon, and aremovable tripping-bar bent to form two arms, one of which is adapted tobe inserted between said flanges and the other beneath a door or othermoving part.

6. A burglar-alarm comprising a bell, a motor-spring, a system ofgearing, including an escapement, a clapper for said bell connected tosaid escapement, a locking-spring having a lug or projection thereonadapted to engage the clapper-arm for rendering said motorspringinoperative, a push-bar connected to said locking-spring for moving saidlug out of engagement with said clapper-arm, said push-bar beingprovided with notches or cutaway portions on opposite sides adjacent toits'outer end, a plate secured to the outer end of said push-bar havinginwardly-extending flanges thereon, and a tripping-bar bent to form twoarms, one of which is adapted to be inserted between said flanges and isprovided with a slot adapted to embrace the cut-away portion 0t saidpush-bar and the other adapted to be inserted beneath a door or othermoving part.

In testimony whereof I have hereunto set my hand in the presence of twosubscribing Witnesses.

HENRY CLAY JOHNSON.

Witnesses:

GEO. W. REA, ROBERT EVERETT,

